Interesting compositions are (for me) certainly those that contemplate the use of prepared instruments and instruments tuned in the usual way; the unique use of those
prepared (which then always depends on how they are used) sometimes seems like an end in itself, and precisely because there is no preparation in most cases among those
who listen to them, they move past it.
I was thinking of something, just off the top of my head, without engaging in destructive reasoning: is it possible that an interval smaller than a semitone can be perceived with a delay,
precisely because of the lack of preparation the brain normally has in processing what is filtered by the ear?
For this reason, when 3/4 notes are played consecutively, but also 2 at the same time and the other 2 "in series," so to speak, is a certain amount of time necessary
(different from person to person) to manage to perceive the range of difference between 2 intervals of this type?
And also, how much does the conditioning regarding the perception of familiar sounds involve "the search" for the "recognizable" interval, and (before it slips my mind, concentration here
is always at a crossroads) if the ear finally, through the brain, does not create a "derivative" starting from intervals of some commas, which when added together form an interval of a range
similar to or closer to the semitone and the tone? (precisely due to a sort of necessity, albeit subjective, of the brain that processes what is filtered by the ear).
These questions came to me thinking about what has been written regarding Ligeti's work, and what he himself seems to have said.
I think that other factors also come into play in this discussion, such as duration, overlap, and the dynamics of the notes: a part played staccato, and very quickly,
will require a longer time (perhaps) to be assimilated, processed, and made understandable compared to a series of held notes, for which (paradoxically) there is time to
"understand" their difference, and probably reducing the "reaction" time (assimilation and processing).